State lawmakers enacted the law last year in the hopes it would help revive Chicago's struggling convention industry.
On Thursday, a judge ruled that the National Labor Relations Act prevents the state from adopting work rules that interfere with collective bargaining.
"I thought there were shortcomings in that bill. I said so to the legislative leaders and members who advocated for it. They decided to plow ahead," Quinn said.
Quinn says this issue needs to be straightened out, and that getting more convention business in Illinois is a big priority.